The Metabolic Syndrome (Emperor) Wears No Clothes

There are several key features of the metabolic syndrome that virtually all interested individuals and organizations agree upon. First, that certain “metabolic” factors tend to associate with each other more often than chance would dictate. Second, these risk factors taken alone or in any possible combination are associated with an elevated risk for cardiovascular disease (CVD) and diabetes. Third, there is no definitive treatment for the “syndrome” per se. Rather, therapy is individualized according to the degree to which any specific risk factor(s) is present in a patient, and everyone with any risk factor(s) should be given lifestyle modification counseling. Finally, despite over 10,000 articles on the subject, there is much missing information. It is this last fact that has lead to the concern and consternation voiced by some organizations (1) and individuals (2– 6). That is, the basic question is whether we know enough about this constellation of risk factors to warrant adopting a unique clinical construct that has value to either physicians or patients. After all, the fundamental purpose of a medical label (diagnosis) is to inform physicians and/or patients to take (or not take) action that would otherwise be different. In this issue of Diabetes Care (7) and recently elsewhere (8), Scott Grundy, MD, PhD, perhaps the chief proponent of the syndrome as a clinical construct, defends its existence with a variety of arguments. Although he suggests the basic disagreement is one of “differences in perspectives and biases [between the] cardiovascular and diabetes communities” (7) and that it may boil down to “how to integrate the metabolic syndrome into concepts of insulin resistance, pre-diabetes, and type 2 diabetes” (8), in fact, the issues are much more fundamental, speak to the lack of a solid evidence base, and raise concerns that are critical to a core premise of a diagnostic label, i.e., its clinical utility.